Liver-Targeted siRNA Lipid Nanoparticles Treat Hepatic Cirrhosis by Dual Anti-Fibrotic and Anti-Inflammatory Activities.

Previous studies on the treatment of hepatic cirrhosis have been focusing on how to inhibit liver fibrosis, while ignoring liver inflammation, a key and underlying factor that promotes cirrhosis. High mobility group box-1 (HMGB1) protein, a pro-inflammatory factor and fibroblast chemokine, can promote the proliferation of hepatic stellate cells (HSCs) and the development of hepatic inflammation and fibrosis, playing a key role in the cirrhosis formation. In this study, we prepared pPB peptide (C*SRNLIDC*) -modified and HMGB1-siRNA-loaded stable nucleic acid lipid nanoparticles (HMGB1-siRNA@SNALP-pPB) to effectively treat hepatic cirrhosis by their dual anti-fibrotic and anti-inflammatory activities. The pPB peptide-modified and heat shock protein 47 (HSP47) -siRNA-loaded stable nucleic acid lipid nanoparticles (HSP47-siRNA@SNALP-pPB), which have only anti-fibrotic effect without anti-inflammatory effect, was used as control. The results demonstrated that HMGB1-siRNA@SNALP-pPB were actively targeted to HSCs by the mediation of pPB peptide, effectively silenced the HMGB1 gene, inhibited the activation and proliferation of HSCs, reduced the release of HMGB1 protein, inhibited the collagen deposition and fibrosis formation in the liver, and significantly prolonged the survival time of cirrhotic mice models. HMGB1-siRNA@SNALP-pPB showed a stronger therapeutic effect on liver cirrhosis than HSP47-siRNA@SNALP-pPB. This study provides an actively targeted siRNA delivery system for cirrhosis treatment based on the dual anti-fibrotic and anti-inflammatory effects. In addition, this study clarified the role of inflammatory problems in cirrhosis treatment in addition to liver fibrosis, providing a useful idea and scientific basis for the development of cirrhosis treatment strategies in the future.